Investigating the feasibility of berry production in Central Oregon under protected and unprotected culture

Progress report for OW18-020

Project Type: Professional + Producer
Funds awarded in 2018: $49,998.00
Projected End Date: 03/31/2021
Grant Recipient: Oregon State University
Region: Western
State: Oregon
Principal Investigator:
Clare Sullivan
Oregon State University
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Project Information


Central Oregon’s challenging growing conditions include: 1) a very short growing season (70-
100 days); 2) average annual precipitation of ~11 inches; 3) drastic swings in diurnal
temperatures; 4) possibility of frost anytime of year; and 5) sandy soils low in organic matter
(Detweiler, 2016). The USDA plant hardiness zones in Central Oregon range from 3 to 5, with
pasture and forages as the traditional crops grown in the area.
Despite the challenging growing conditions, there is fresh-market produce grown in Central
Oregon, and there is strong demand from the community through farmer markets, CSAs,
restaurant buyers, and wholesale accounts (Rahe et al., 2017). While some vegetables are grown
very well in the region, there is almost no fruit being produced in Central Oregon, despite strong
demand. Growers report that farmers’ market patrons with federal nutrition assistance benefit
vouchers want to use their vouchers to purchase berries (Jim Fields and David Kellner-Rode,
personal communication). According to Nicole Sanchez from OSU Extension in Klamath
County, there is also a severe lack of fresh berries available for purchase in Klamath County.
Raspberries and strawberries are the most suitable berries for Central Oregon due to their cold
hardiness (Detweiler and Strik, 2008), but yield loss due to winter injury and frosts are a major
concern. Elsewhere in the US, protected culture has been used to extend the berry growing
season and improve yields (Rowley et al., 2009 & 2010). In central Oregon, high tunnels are
currently used to grow multiple high-value vegetable crops in one season, so farmers are not
likely to plant a perennial crop in a high tunnel unless proven profitable. This project aims to
determine whether berry production in Central OR is an economically viable enterprise, and if
high tunnels are a justified expense to increase profitability and fruit quality.

Project Objectives:

1. To evaluate raspberry and strawberry production in both protected and unprotected
culture systems in Central OR, including berry yield and quality, in order to help growers
choose the most successful production systems.
2. To compare multiple cultivars of raspberry and strawberry for suitability to Central OR,
including adaptability, berry yield, and quality, in order to help growers make cultivar
selections most likely to lead to production success.
3. To perform economic evaluation of both protected and unprotected berry production in
Central OR, and determine whether protected culture is a justified investment.
4. To maintain records of pest management problems as they occur in both protected and
unprotected culture.
5. To conduct local, regional and interstate outreach of berry crop research in the high
desert through field days, workshops, presentations, and fact sheets.
6. To increase the supply of fresh fruit as a healthy food option for Central OR residents


Click linked name(s) to expand


Materials and methods:

The research portion of this project began in May 2019 when the raspberries and strawberries were planted. The evaluation of berry production systems and varieties is being conducted at seven sites across the region using a mother-daughter experimental design. In this design, the mother trial includes all of the possible research treatments, while the daughter trials only include those treatments of interest to each farmer (Casler, 2015). The mother-daughter experimental design allows farmers to participate in research with fewer financial and labor restrictions, and participants are free to choose the treatments of greatest interest and value to their farm.

The mother trial is managed and evaluated by the PI (Clare Sullivan) and located in Alfalfa, OR (Deschutes County). Seven cooperating farms are involved in the study, and each farm is hosting a research site. Six of the cooperating farms are located in Deschutes County, and one is located in Crook County. All eight sites are managed organically, and soil amendments were applied based on soil tests and in consultation with the PI. 

Mother trial design

Two berry trials were established on a farm in Alfalfa, OR in May 2019. Raspberries and strawberries were planted according to recommended commercial practices (Marvin et al., 2017; Rowley et al., 2009 & 2010). Four strawberry varieties were planted as bare rootstock in a high tunnel (14x45ft structure, Fig 1) and the open field on May 6. All of the varieties were cold-hardy and day-neutral types: ‘Albion’, ‘Evie 2’, ‘Mara des Bois’, and ‘Seascape’. Strawberries were planted directly into landscape fabric at 1ft-spacing in double rows, with beds spaced 4ft apart. Individual plot size measured 10ft indoor, and 20ft outdoor. First inflorescences were removed until early June in order for the strawberry plants to get established vegetatively before entering the productive phase. Runners were removed all season to maintain each strawberry plant as one mother plant. Strawberry plots were irrigated using two drip irrigation lines per bed; emitters on the drip lines were at 12″ spacing.

Four raspberry varieties were planted as bare rootstock in a separate high tunnel (30x45ft structure, Fig 2) and the open field on May 8. All of the raspberry varieties chosen were cold-hardy and primocane-bearing types: ‘Anne’, ‘Caroline’, ‘Heritage’, ‘Joan J’. Raspberries were planted at 2ft-spacing within rows that were planted 8ft apart, and landscape fabric was used between the rows for weed suppression. Individual plot size measured 10ft indoor, and 15ft outdoor. Trellis systems were installed to support the raspberries once they were tall enough. Raspberry plots were irrigated using one drip line per bed; emitters on the drip lines were at 12″ spacing.

Picture showing three rows of strawberries planted in a high tunnel
Figure 1. Inside the strawberry high tunnel, structure is 14 x 45ft.
Picture showing raspberry and strawberry high tunnels in the background, and outdoor strawberry planting in the foreground
Figure 2. Raspberry high tunnel on the left (30 x 45ft gothic-style), strawberry high tunnel on the right right. Outdoor raspberries top left, outdoor strawberries foreground of photo.

The experiments were randomized complete block designs, with three replicates in the strawberry trial and four replicates in the raspberry trial. The plots were managed using organic practices. Pre-plant fertility was met with poultry manure, feather meal, gypsum, and compost; they also received liquid fish fertilizer twice over the growing season. Thrip pressure was very high in mid-July and the plots were sprayed with Mycotrol, an organic insecticide (active ingredient Beauveria bassiana). Shade cloth was installed on both of the high tunnels once temperatures were consistently over 85 degrees Farenheit to protect the plants. 

Berries were harvested once a week when production began, and then twice a week when berries were in full production. Harvested berries were separated into ‘marketable’ and ‘unmarketable’ in order to calculate percent cull. Marketable and unmarketable berries per plot were then counted and weighed to calculate yield per plot and fruit size (weight/berry). In order to compare yield across treatments, marketable weight was normalized per 10 plants. Total marketable yield per treatment was the accumulated yield over the growing season, normalized per 10 plants. Data were subjected to analysis of variance, and treatment means were compared using Tukey’s honest significant difference test (P < 0.05).

Daughter trial designs

Seven farmer collaborators hosted trials with the same berry cultivars used in the mother trial and followed the same recommended commercial practices. The size and type of high tunnel varied by farm, some growers only grew raspberries or strawberries, and growers compared different numbers of cultivars. All berries were planted in late April or early May of 2019. Two farms are comparing protected and unprotected raspberry production; five farms are comparing protected and unprotected strawberry production; one farm is comparing different raspberry cultivars grown outdoor; and one farm is comparing different strawberry cultivars grown outdoor. 


Research results and discussion:

Mother Trial Results

Strawberry Trial

The first pick of fruit for both outdoor and indoor production was July 19, 2019. It was not until mid-August the strawberries started producing consistently, and indoor production increased at a faster rate than outdoor production (Figs 3-6). Three of the strawberry varieties peaked in production August 20, but Albion peaked in September (Fig 3). Rain and cold temperatures in mid-September resulted in dirty and mushy fruit, which is reflected by a drop in marketable yield (Figs 3-6). Freezing temperatures at the end of September/early October ended the season’s harvest. Overall, marketable yield was significantly higher for indoor production (10lbs/10 plants) than outdoor production (8lbs/10 plants), and in some varieties total yield increase indoor was more than 40% (Table 1).

Strawberry fruit size differed by variety and also by production system (Table 1). Strawberry fruit size was on average 18% greater for indoor production (13 g/berry) than outdoor production (11 g/berry). Albion and Evie 2 had significantly larger fruit size than Seascape and Mara des Bois (Table 1). Mara des Bois is known to be a smaller berry, and in our trials it averaged ~50% weight of the other berries. Fruit size is significant for a grower because the larger the berry fruit size the fewer berries needed to fill a pint, and the lower the labor requirements.

Evie 2 stood out as the highest yielding variety (12lbs/10 plants), especially grown indoor. However, Evie 2 had a softer berry that was easily bruised while handling, and had a significantly higher cull rate than other varieties (average 23% cull vs. 12-17%). Also, many taste test participants found the flavor of Evie 2 to be bland. Albion had firm fruit and was a favorite in many taste tests, but the first-year yield was significantly lower than other berries. Seascape was not as firm as Albion, but had a very nice flavor and a consistent yield indoor and outdoor (Table 1). While many people liked the flavor of Maras des Bois, its small size made harvest too time consuming to be profitable.   

Graphs depicting strawberry marketable yield (g/10 plants) over growing season, individual charts by variety comparing indoor and outdoor production
Figure 3. Strawberry marketable yield (g/10 plants) over growing season. Indoor vs. outdoor production by variety.

Table 1. Strawberry data comparing four varieties grown outdoor (field) vs. indoor (high tunnel). Data is an average of three replicates.


Average fruit size(g/berry)

Total marketable yield (lbs/10 plants)

Total % yield increase indoor

Highest single yield (lbs/10 plants)

Total % cull

(by weight)1












14 a2

16 a

5.6 b

8.1 b






Evie 2

13 a

15 a

9.7 a

14.2 a






Mara des Bois

6 c

8 c

8.8 a

9.4 b







12 b

13 b

8.2 a

8.9 b






1 % cull until Sep 16 harvest, % cull rose dramatically after Sep 16 due to rain and freeze

2 Results in the same column followed by a different letter are significantly different at P < 0.05


Raspberry Trial

Raspberries started fruiting mid-August, but harvest was not consistent until the end of August. As with the strawberries, raspberry production increased more quickly in the high tunnel plots than the outdoor plots (Fig 4). Raspberry production was steadily increasing in late September, but harvest was cut short by freezing temperatures. The last harvest outdoor was September 25, and was also the highest yield for all varieties (Fig 4). The indoor plots survived the freezing temperatures a little longer, and indoor production peaked September 25. The October 2 harvest indoor occurred after a heavy freeze, and nearly all of the berries were culled. Overall, marketable yield of raspberries tended to be higher for indoor production (6.8lbs/10 plants) than outdoor production (4.1lbs/10 plants). In some varieties total yield increase indoor was more than 75% (Table 2).

Raspberry fruit size increased over the growing season in the outdoor plots, from an average of 2.3 g/berry on Aug 12, to 3.7 g/berry on Sep 25. In contrast, fruit size indoor remained fairly steady over the growing season. On average, there was a 12% increase in berry size from outdoor to indoor production (Table 2). Variety had a greater effect on fruit size than production system; Heritage was significantly smaller than other berries, and Joan J was noticeably larger.

Joan J stood out as the highest yielding raspberry variety (12.7lbs/10 plants), especially grown indoor (Table 2). Over the growing season, Joan J out-yielded the other varieties outdoor by 250%, and indoor by 350%. Caroline had the smallest yield, which was surprising because it is marketed as one of the “most productive primocane-bearing raspberries” and is supposed to fruit earlier than Heritage. In our trials, Caroline remained vegetative most of the growing season and yield did not start increasing until mid-September. Heritage is an heirloom variety and yielded lower than the other modern varieties due to its small fruit size. Anne had large, yellow berries and produced fairly well, but the fruit was more delicate and prone to being culled. There was not a clear winner in terms of taste for the berry varieties, but most taste testers liked the flavor of the outdoor raspberries more than the indoor berries.

Graphs depicting raspberry marketable yield (g/10 plants) over growing season, individual charts by variety comparing indoor and outdoor production
Figure 4. Raspberry marketable yield (g/10 plants) over growing season. Indoor vs. outdoor production by variety.

Table 2. Raspberry data comparing four varieties grown outdoor (field) vs. indoor (high tunnel). Data is an average of four replicates.


Average fruit size(g/berry)

Total marketable yield (lbs/10 plants)

Total % yield increase indoor

Highest single yield (lbs/10 plants)

Total % cull

(by weight)












4.1 ab1

4.3 a

3.3 b

4.4 b







3.0 ab

3.9 a

1.7 b

2.1 b







2.3 b

2.4 b

2.5 b

4.5 b






Joan J

4.8 a

4.7 a

9.1 a

16.3 a






1 Results in the same column followed by a different letter are significantly different at P < 0.05

Daughter Trial Results

First year results are still being gathered from the cooperating farms. It proved difficult to have farmers consistently collect berry yield data on their farms, especially since the berries started producing slowly and the farmers or farm workers ate the berries instead of measuring the yield. Discussion at our season wrap-up meeting in November confirmed that grower experience of variety and production system was similar to the results found at the mother trial. Indoor berries flowered and set fruit earlier than outdoor berries, indoor plants had higher berry production per plant, and indoor berries had a longer growing season that outdoor berries. Growers did find a dip in strawberry yield and quality in the heat of the season.

By variety, growers found Evie 2 to be the highest yielding strawberry, but many were unhappy with the fruit quality. They found Evie 2 to be a softer berry that was sensitive to bruising and harder to store for several days. While Mara des Bois produced good yield for growers, they were frustrated with how long it took to pick the berries due to the small size. Some growers had fruit quality issues with Mara des Bois, and ended up with very soft fruit later in the season. Growers found Joan J to be the highest yielding raspberry variety, and were fairly happy with the quality of fruit. Customers at the farmers market favored Anne, the yellow raspberry with big fruit size. 

Preliminary Conclusion

First year results revealed berry yield and quality differences between varieties and production systems. Berry variety had a greater influence on the factors measured rather than indoor vs. outdoor production. Evie 2 was the highest yielding strawberry, although berry quality (flavor and handling) was lower than other berries. Joan J was the highest yielding raspberry and berry quality was quite good. Strawberry and raspberry yields tended to improve in high tunnels as compared to the field, but data from a second year will help determine whether the high tunnel investment is worthwhile. Overall, grower cooperators were impressed with berry production indoor, and based on first year results several of the strawberry-only cooperators said they were interested in planting raspberries in the future. 

Participation Summary
11 Farmers participating in research

Educational & Outreach Activities

10 Consultations
2 On-farm demonstrations
1 Published press articles, newsletters
4 Tours
4 Workshop field days
3 Taste testing events

Participation Summary

49 Farmers
5 Ag professionals participated
Education/outreach description:


Consultations have been conducted individually with each of the seven farms (11 farmers) involved in the research project. Clare Sullivan (PI) consulted on what berry crop type would best suit their operation, helped them choose berry cultivars of interest, and determined nutrient application rates based on their soil tests. In addition to the farms in the study, the PI consulted with three local farms as they made decisions on berry plantings.

Field Tours

In November 2018, the PI organized a tour of commercial berry farms in the Willamette Valley, Oregon for the farmer cooperators involved in the research project. The PI and five farmers visited two commercial berry operations that grew raspberries and strawberries in high tunnels and in the field. One operation was mid-scale and used organic practices, and the other was larger-scale conventional The group received educational information from the two farm managers we visited, including perspective on planting and maintenance, variety selection, considerations for field and high tunnel production, and marketing information. 

During the summer of 2019, the PI organized three field tours for the seven cooperating farms. The group toured Golden Eagle Organics in Bend, Windflower Farm in Alfalfa (main research site), and Boundless Farmstead in Alfalfa. At Golden Eagle Organics, farmers observed raspberry and strawberry production in a gothic-style high tunnel, a caterpillar tunnel, and the open field; and learned about a small-scale fertigation system. At Windflower Farm, farmers observed raspberry and strawberry production in gothic-style and low-cost PVC high tunnels, and the open field; and learned about three different raspberry trellising systems. At Boundless Farmstead, farmers observed strawberry production in a quonset-style high tunnel and the open field, and saw a side-by-side comparison of first and second year strawberry plantings.    

Workshops/Field Days

In February 2019, Tanya Murray from Oregon Tilth gave a “Cost of Production” Workshop at the OSU Extension office in Redmond (Central Oregon). Three of the cooperating farmers involved in the berry project attended the workshop and learned labor tracking skills to implement over the growing season.

In March 2019, the PI hosted a Berry Production Workshop in Redmond, OR, taught by the OSU Berry Specialist Dr. Bernadine Strik. The workshop was open to the public and was an in-depth overview of raspberry and strawberry production, including: berry type and morphology; berry establishment and maintenance; raspberry pruning and trellising; and berry nutrient management. Attendees reported significant knowledge gained from the workshop, and berry project cooperating farmers indicated that it set them up very well for the season. 

Also in March 2019, the PI hosted an advanced high tunnel workshop taught by two Utah State University Researchers. The workshop was open to the public and the information was extremely relevant to high desert production systems. Brent Black (USU Berry Specialist) presented specifically on high tunnel raspberry and strawberry production. 

In September 2019, the PI hosted a Berry Field Day at the main research site (Windflower Farm). The field day was open to the public and the PI shared observations from the berry research trial, including: land prep; planting techniques; plant maintenance; pest management; trellis systems high tunnel construction; variety differences; and production system differences. 

On-Farm Demonstrations

The PI hosted a low-cost high tunnel construction demonstration at Windflower Farm (main research site) in April 2019. Design plans from Utah State University Researchers were used to build a 14 x 45ft high tunnel out of PVC, and the public was invited to take part in the high tunnel construction. A second demonstration was hosted at Windflower Farm in May 2019 to teach proper planting techniques for strawberries and raspberries. 

Taste Testing Events

One of the objectives of this research is to evaluate the quality of the berries, not just the quantity produced. The PI hosted three different taste testing events at the end of the 2019 growing season and recorded participants’ opinions on berry flavor and texture. Eight raspberry and strawberry treatments were compared; four varieties and two production systems (indoor vs. outdoor). One taste testing event was for the cooperating farmers, one was open to the public at Windflower Farm, and one was for buyers. It was impractical to host a tasting event for buyers, therefore the PI brought berries to them; the berries were evaluated for their quality by three chefs/bakers and one wholesale buyer. 

Published Report

A report on the preliminary results of the Berry Project was submitted to the 2019 Central Oregon Agriculture and Extension Center Annual Report, and will be published end of January 2020.  

Upcoming Activities 

A hybrid online/in-person cost of production program, ‘Know Your Costs to Grow’, is starting January 2020 in Central Oregon, and three of the berry project cooperating farms are signed up for the program. This will be continuing education from 2019 on tracking the costs of producing different crops, and berry growers will use this training to track production costs of raspberries and strawberries. The program will run the entire 2020 growing season and conclude with a follow-up workshop end of 2020.

The PI will present information from the berry project at the OSU Small Farms Conference in Corvallis, OR in February 2020. In March 2020, the PI will host a berry production workshop in Redmond, OR that is open to the public and will advertised across the state. The workshop will include first year results from the berry project and berry production overview information from Dr. Strik’s workshop in 2019. There will be additional field days and tours hosted at the berry research sites in 2020, and articles published in the OSU Small Farms Newsletter. Extension and peer-reviewed publications will be written after data is collected from second year results. 

Learning Outcomes

25 Farmers reported changes in knowledge, attitudes, skills and/or awareness as a result of their participation
Key changes:
  • Gained knowledge of establishing strawberries under plastic mulch, both in high tunnels and in the field

  • Learned the pros and cons of growing raspberries using fabric row cover

  • Awareness of the considerations for choosing berry varieties related to marketing

  • Knowledge about the different types of raspberries and strawberries, including their morphology

  • Knowledge of how to establish, prune, and train a raspberry planting

  • Knowledge of what is required to establish and manage a strawberry planting

  • Knowledge of the nutrient management requirements for berry crops

  • Awareness of the pest pressure for berry production in Central Oregon (both in high tunnel and open field)

  • Performance differences of growing berries in high tunnels vs. the open field

Project Outcomes

7 Farmers intend/plan to change their practice(s)
Project outcomes:

There are no project outcomes to report at this time.

Any opinions, findings, conclusions, or recommendations expressed in this publication are those of the author(s) and do not necessarily reflect the view of the U.S. Department of Agriculture or SARE.